Light Emitting Diodes (“LEDs”) are gaining favor as light sources in the automotive industry because of increased efficiency and longevity over traditional incandescent or arc discharge light sources.
A current method of using LED light sources in automobile lamp assemblies involves creating a printed circuit board (“PCB”), an electrically insulating material with an inlaid conductive lead frame. The conductive lead frame defines a circuit, to which LED light sources and related drive components are attached. The conductive lead frame also creates electrical attachment points, for terminals or a wire harness, to enable electricity from outside the lamp to be carried to the LED light sources. The LED light sources and related drive components are attached to the side of the PCB facing outwardly. The PCB is then attached to the inside of the lamp assembly.
The attachment of LED light sources to a PCB requires the manufacture of the PCB, attachment of the LED light sources, related drive components to the PCB; attachment of the PCB to the inside of the lamp assembly, and the attachment of the terminals or the wire harness to connect to the automobile's electrical system. The addition of a PCB to the lamp assembly increases the overall weight of the lamp assembly, adds additional complexity to the lamp assembly, and increases the overall size requirements of the lamp assembly.
An improved lamp assembly would eliminate the need for a PCB, and instead place the conductive lead frame directly on the inside of the lamp housing. Surface mounted LED light sources would then be attached directly to the lead frame in the housing. The placement of the conductive lead frame directly on the inside of the housing removes the requirement for a separate PCB, reducing the complexity and the overall weight of the lamp assembly, and also allows the lamp assembly to be more compact. A more compact lamp assembly allows the automobile manufacturer more design flexibility and potential savings in sheetmetal and manufacturing costs.